Hybrid nanofluids are of great importance in the field of industry due to high effective thermal conductivity which causes high rates of heat transfer. The current article investigates the impact of ...variable magnetic field and chemical reaction of
MWCNT/Fe
3
O
4
–water hybrid nanofluid over an exponentially shrinking porous sheet with slip boundary conditions. Suitable transformations convert the governing equations into coupled nonlinear ordinary differential equations. Further, these equations are solved by the help of shooting technique. The influences of operating parameters on the flow domain as well as force coefficients and rates of heat and mass transfers are computed and shown through graphs and tables. It is found that hybridity augments the temperature and concentration profiles. Further, suction/injection parameter enriches the skin friction coefficient, but reverse trend is observed for velocity slip parameter.
Zr–Nb alloy is used as the pressure tube in pressurized heavy water reactors (PHWR). Prolonged neutron irradiation of the pressure tubes leads to the formation of a long-lived radioisotope 94Nb. ...Thus, the discharged pressure tubes possess huge 94Nb activity which persists for a prolonged period.If these discharged pressure tubes come in contact with ground water, 94Nb isotope may leach and migrate and this can lead to a long-term radiological impact in the environment.In the present study, we have explored the capability of laterite as a filler material for the containment and retarding the migration of 94Nb. In this regard, detailed characterization of the laterite soil was carried out using energy dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD), fourier transform infra-red spectrometry (FTIR), total cation exchange capacity determination, zeta potential measurement and thermogravimetric analysis (TGA). The sorption study of 94Nb on laterite was carried and the effects of different physico-chemical parameters like pH, ionic strength, temperature and equilibration time were evaluated. Ionic strength, temperature and time dependent sorption studies assist to explore the probable sorption mechanism of 94Nb on laterite, which helps in understanding the migration behaviour of 94Nb in natural aquatic environment. This study suggests that laterite is a promising material in containment of 94Nb isotope owing to its good cation exchange behaviour in the acidic medium and ability to form surface complex in the neutral medium.
•94Nb is a long-lived activation isotope generated in Zr–Nb pressure tube of PHWR.•Sorption behaviour of 94Nb on laterite and effects of various parameters was studied.•Ion exchange is the mechanism behind the sorption in acidic pH.•Surface complexation is the driving force for the sorption in neutral and basic pH.•Laterite found to be a promising filler or geochemical barrier material for 94Nb.
This article studies the effect of nanoparticle aggregation on the 3D flow of titanium nanoliquid based on ethylene glycol
(
C
2
H
6
O
2
-
TiO
2
)
due to an exponentially elongated surface. Thermal ...analysis is carried out considering linear thermal radiation, Joule heating, and mechanisms of the heat source/sink, while the aspect of the homogeneous single-order chemical reaction is included in the analysis of the solute. The variable magnetic field is also accounted. The modified Maxwell model (Maxwell–Bruggeman) is implemented to estimate the effective conductivity of the nanoliquid. The displayed equations are moderated in quantities without dimensions. The 2-point nonlinear boundary value problem (BVP) is solved by the shooting procedure. The importance of effective parameters is described through graphs. Numerical data are presented to study the friction factor, the heat transfer rate, and the mass transfer rate. It has been established that the aggregation of nanoparticles significantly improves the thermal field. Furthermore, the effect of magnetism is more in ordinary fluid than in nanofluid.
Bidirectional inductive power transfer (IPT) systems are suitable for applications that require wireless and two-way power transfer. However, these systems are high-order resonant networks in nature ...and, hence, design and implementation of an optimum proportional-integral-derivative (PID) controller using various conventional methods is an onerous exercise. Further, the design of a PID controller, meeting various and demanding specifications, is a multiobjective problem and direct optimization of the PID gains often lead to a nonconvex problem. To overcome the difficulties associated with the traditional PID tuning methods, this paper, therefore, proposes a derivative-free optimization technique, based on genetic algorithm (GA), to determine the optimal parameters of PID controllers used in bidirectional IPT systems. The GA determines the optimal gains at a reasonable computational cost and often does not get trapped in a local optimum. The performance of the GA-tuned controller is investigated using several objective functions and under various operating conditions in comparison to other traditional tuning methods. It was observed that the performance of the GA-based PID controller is dependent on the nature of the objective function and therefore an objective function, which is a weighted combination of rise time, settling time, and peak overshoot, is used in determining the parameters of the PID controller using multiobjective GA. Simulated and experimental results of a 1-kW prototype bidirectional IPT system are presented to demonstrate the effectiveness of the GA-tuned controller as well as to show that gain selection through multiobjective GA using the weighted objective function yields the best performance of the PID controller.
The effects of monosubstitution on the aromaticity of benzene are assessed using a number of different quantitative schemes. The ability of the mobile π-electrons to respond to an external magnetic ...field is evaluated using several variants of the NICS scheme which calculate the shielding of points along the axis perpendicular to the molecule. Another class of measures is related to the drive toward the uniformity of C-C bond lengths and strengths. Several energetic quantities are devised to approximate an aromatic stabilization energy and the tendency of the molecule to maintain planarity. There is a lack of consistency in that the various measures of aromaticity lead to differing conclusions as to the effects of substituents on the aromaticity of the ring.
Natural bioflavonoids are an essential component of dietary supplements possessing antimicrobial properties. Many of the bioflavonoids have resulted in positive antitumor, anticancer, antibacterial, ...antifungal, anti-inflammatory properties, but the efficacy remains low due to toxicity at the molecular level whereas antiviral property limits to negative. The synergistic link between nanoscience and flavonoid chemistry enhances the epidemiological properties of flavonoid and also diminish the antimicrobial resistivity (AMR) by forming their hybrid nanocomposites. Nanochemistry uses various nanocomposite and nanomaterials for biosensing the flavonoids and their delivery as a drug. The quercetin flavonoid and its derivatives such as rutin, and myricetin are used for sensing and drug delivery. Quercetin with 15Carbon-5Hydroxyl chemical scaffold has been explored for a few decades for the development of hybrid nanocomposite and nanomaterial with metallic as well as organic nano co-composites. This quercetin flavonoid based hybrid nanocomposites seemed to show a significant effect on In vitro and some animal model processes along with attenuating lipid peroxidation, platelet aggregation, and capillary permeability actions. This review mainly focused on the hybrid nanoscience of quercetin bioflavonoid and its application in numerous biological, material fields with a future perspective.
The emergence of diseases and mortalities in aquaculture and development of antibiotics resistance in aquatic microbes, has renewed a great interest towards alternative methods of prevention and ...control of diseases. Nanoparticles have enormous potential in controlling human and animal pathogens and have scope of application in aquaculture. The present investigation was carried out to find out suitable nanoparticles having antimicrobial effect against aquatic microbes. Different commercial as well as laboratory synthesized metal and metal oxide nanoparticles were screened for their antimicrobial activities against a wide range of bacterial and fungal agents including certain freshwater cyanobacteria. Among different nanoparticles, synthesized copper oxide (CuO), zinc oxide (ZnO), silver (Ag) and silver doped titanium dioxide (Ag–TiO₂) showed broad spectrum antibacterial activity. On the contrary, nanoparticles like Zn and ZnO showed antifungal activity against fungi like Penicillium and Mucor species. Since CuO, ZnO and Ag nanoparticles showed higher antimicrobial activity, they may be explored for aquaculture use.
Magnetic luminescent hybrid nanoparticles Fe3O4/BaMoO4:Dy3+ (MLHNPs) were successfully synthesized by the co-precipitation method using ethylene glycol. The MLHNPs are functionalized with ...β-cyclodextrin (CD) using 3-aminopropyl triethoxysilane (APTES). The surface functionalization of nanoparticles and their conjugation have been confirmed via powder XRD, FTIR, HRTEM, and PL analyses. The feasibility of functionalized MLHNPs as nanocarriers for hydrophobic drugs (triazole derivatives) was verified by studying the uptake and release profile using a triazole derivative as a hydrophobic drug. In addition, the photoluminescence spectroscopy results confirmed the optical imaging capability of MLHNPs. The outcomes of loading and release disclose that this system is likely to be a suitable tool as a hydrophobic drug carrier.
Circulating tumor cells (CTCs) may have utility as surrogate biomarkers and "virtual" biopsies. We report the clinical significance and molecular characteristics of CTCs and CTC clusters, termed ...circulating tumor microemboli (CTM), detected in patients with small-cell lung cancer (SCLC) undergoing standard treatment.
Serial blood samples from 97 patients receiving chemotherapy were analyzed using EpCam-based immunomagnetic detection and a filtration-based technique. Proliferation status (Ki67) and apoptotic morphology were examined. Associations of CTC and CTM number with clinical factors and prognosis were determined.
CTCs were present in 85% of patients (77 of 97 patients) and were abundant (mean ± standard deviation = 1,589 ± 5,565). CTM and apoptotic CTCs were correlated with total CTC number and were detected in 32% and 57% of patients, respectively. Pretreatment CTCs, change in CTC number after one cycle of chemotherapy, CTM, and apoptotic CTCs were independent prognostic factors. Overall survival was 5.4 months for patients with ≥ 50 CTCs/7.5 mL of blood and 11.5 months (P < .0001) for patients with less than 50 CTCs/7.5 mL of blood before chemotherapy (hazard ratio = 2.45; 95% CI, 1.39 to 4.30; P = .002). Subpopulations of apoptotic and of proliferating solitary CTCs were detected, whereas neither were observed within cell clusters (CTM), implicating both protection from anoikis and relative resistance to cytotoxic drugs for cells within CTM.
Both baseline CTC number and change in CTC number after one cycle of chemotherapy are independent prognostic factors for SCLC. Molecular comparison of CTCs to cells in CTM may provide novel insights into SCLC biology.
This work presents the synthesis of a hybrid core-shell structured Fe(0)@Fe oxide and Mn(0)@Mn oxide (ZVIM) nanocomposite by an ultrasonically assisted hydrothermal process for decontamination of ...arsenic in groundwater. Our material possesses a unique core-shell structure with zero-valent Fe and Mn in the core encapsulated by a thin layer of their respective oxides. Herein, the synthesized material utilizes the synergetic effect of Mn-oxide layers of zero-valent manganese (ZVM) to oxidize As(
iii
) to As(
v
) and iron oxide layers of zero-valent iron (ZVI) for sequestration of total arsenic. The maximum adsorption capacity of ZVIM is calculated to be 58.9 mg g
−1
and 101.95 mg g
−1
for As(
iii
) and As(
v
), respectively, which is greater than that of the individual zero-valent manganese and zero-valent iron. The uptake kinetics of both As(
iii
) and As(
v
) show >80% removal within a reaction time of 20 minutes. The adsorption kinetics follow a pseudo-second order model, suggesting the chemisorption nature of the adsorption process. FTIR and XPS analyses reveal the mechanism of surface interaction of the adsorbent with arsenic species. Furthermore, the effectiveness of our adsorbent is revealed by groundwater tests where the final arsenic concentrations in samples were reduced below the WHO limit for drinking water.
A unique core-shell structured Fe(0)@Fe oxides and Mn(0)@Mn oxides (ZVIM) nanocomposite was synthesized and utilized for effective remediation of arsenic contaminated drinking water.
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